1. Field of the Invention
This invention relates to an open wireless architecture terminal design, focusing on the open baseband processing platform to support different existing and future wireless communication standards through the multi-dimensional open baseband processing modules with open interface parameters and baseband management systems. The invention includes multi-layer open system architecture to maximize the system flexibility and minimize the terminal power consumption, so as to provide an integrated and converged next generation wireless and mobile communication terminal system.
2. Description of the Related Art
Second-generation (2G) mobile systems were very successful in the previous decade. Their success prompted the development of third-generation (3G) mobile systems. While 2G systems such as GSM, IS-95, and cdmaOne were designed to carry speech and low-bit-rate data, 3G systems were designed to provide higher-data-rate services. During the evolution from 2G to 3G, a range of wireless systems, including GPRS, IMT-2000, Bluetooth, WLAN, and HiperLAN, have been developed. All these systems were designed independently, targeting different service types, data rates, and users. As these systems all have their own merits and shortcomings, there is no single system that is good enough to replace all the other technologies. Instead of putting efforts into developing new radio interfaces and technologies for 4G (fourth generation) systems, which some researchers are doing, we believe establishing 4G systems that integrate existing and newly developed wireless systems into one open platform is a more feasible option.
Researchers, from all over the world, are currently developing frameworks for future 4G mobile networks. Different research programs, such as Mobile VCE, MIRAI, and DoCoMo, have their own visions on 4G features and implementations. Some key features (mainly from the users' point of view) of 4G mobile networks are stated as follows:    High usability: anytime, anywhere, and with any technology    Support for multimedia services at low transmission cost    Personalization    Integrated services
Next generation wireless and mobile networks (meaning 4G mobile networks and beyond) are all-IP based heterogeneous networks that allow users to use any system at any time and anywhere. Users carrying an integrated open terminal can use a wide range of applications provided by multiple wireless networks, and access to various air interface standards. Second, next generation mobile systems provide not only telecommunications services, but also data and multimedia services. To support multimedia services, high-data-rate services with good system reliability will be provided. At the same time, a low per-bit transmission cost will be maintained. Third, personalized service will be provided by this new-generation network. It is expected that in future, users in widely different locations, occupations, and economic classes will use the services. In order to meet the demands of these diverse users, service providers should design personal and customized services for them. Finally, next generation mobile systems also provide facilities for integrated services. Users can use multiple services from any service provider at the same time based on the open services architecture.
This vision from the user perspective can be implemented by integration of these different evolving and emerging wireless access technologies in a common flexible and expandable platform to provide a multiplicity of possibilities for current and future services and applications to users in a single terminal. Systems of future mobile networks will mainly be characterized by a horizontal communication model, where different access technologies as cellular, cordless, WLAN type systems, short range wireless connectivity, broadband wireless access systems and wired systems will be combined on a common platform to complement each other in an optimum way for different service requirements and radio environments which is technically called “Open Wireless Architecture (OWA)”.
In order to use the large variety of services and wireless networks in next generation wireless and mobile systems, open user terminals are essential as they can adapt to different wireless networks by reconfiguring themselves. This eliminates the need to use multiple terminals (or multiple hardware components in a terminal). The most promising and optimal way of implementing such multimode and multi-standard user terminals is to adopt the aforementioned open wireless architecture (OWA) approach.
OWA defines the open interfaces in wireless networks and systems, including baseband signal processing system, RF system, networking, and service and application, so that the system can support different wireless industrial standards and integrate the various wireless networks into an open broadband platform. For comparison, Software Defined Radio (SDR) is only a radio in which the operating parameters including interalia frequency range, modulation type, and/or output power limitations, etc can be set or altered by software. Therefore, SDR is just coupling different wireless systems into a reconfigurable radio without defining an open interface within the converged wireless platform. SDR consumes much more power when the number of supported wireless standards increase, especially in the RF system and baseband processing systems.
Like open computer architecture in the computer system, the aforementioned OWA shares all the open system resources including hardware and software by mapping different wireless standards to the open interface parameters of baseband, RF and networks. Each OWA system module is an open module, rather than any standard-specific module, and can be easily reconfigured to maximize the system performance, and minimize the power consumption.
To migrate current systems to such an advanced open wireless system with the features mentioned above, we have to face a number of technical challenges in the open baseband processing:    Terminal design is much hard than base station design due to its limitation of power consumption, chip area, and processing capability,    Open architecture requires full flexibility in baseband processing which normally can be handled by general-purpose processors and digital signal processors. However, these processors consume more power with less efficiency in system performance.    Application-specific integrated circuits (ASIC) is a very efficient processor and consumes low power compared to genera-purpose processors and DSPs, but without flexibility in supporting different wireless standards, because ASIC is normally a standard-specific implementation solution.    Open Wireless Architecture demands efficient baseband processing management system to optimize the open processing modules and system performance.
Such an open baseband processing architecture of the terminal design as provided by the present invention provides an optimal solution to manage the baseband processing tasks for the next generation mobile communication terminals integrating and converging different wireless standards based on the open wireless architecture.